Structure of Procedures

The body of a procedure consists of a compound statement.

A compound statement consists of a BEGIN and an END, enclosing a set of SQL statements. Semicolons delimit each statement.

• SQL Statements Allowed in Procedures
  You can use almost all SQL statements within procedures:
• Parameter declaration for procedures
  Procedure parameters appear as a list in the CREATE PROCEDURE statement. Parameter names must conform to the rules for other database identifiers such as column names. They must have valid data types, and can be prefixed with one of the keywords IN, OUT or INOUT. By default, parameters are INOUT parameters. These keywords have the following meanings:
• Ways to pass parameters to procedures
  You can take advantage of default values of stored procedure parameters with either of two forms of the CALL statement.
• How to pass parameters to functions
  User-defined functions are not invoked with the CALL statement, but are used in the same manner that built-in functions are. For example, the following statement uses the FullName function to retrieve the names of employees: